Along an assembly line, various types of articles, such as for example, diapers and other absorbent articles, may be assembled by adding components to and otherwise modifying an advancing, continuous web of material. For example, in some processes, advancing webs of material are combined with other advancing webs of material. In other examples, individual components created from advancing webs of material are combined with advancing webs of material, which in turn, are then combined with other advancing webs of material. Webs of material and component parts used to manufacture diapers may include: backsheets, topsheets, leg cuffs, waist caps, absorbent core components, front and/or back ears, fastener components, and various types of elastic webs and components such as leg elastics, barrier leg cuff elastics, stretch side panels, and waist elastics. Once the desired component parts are assembled, the advancing web(s) and component parts are subjected to a final knife cut to separate the web(s) into discrete diapers or other absorbent articles.
After the final knife cut, absorbent articles may also undergo a folding process prior to packaging. Pant diapers may also include additional manufacturing steps not used in the manufacture of conventional taped diapers. For example, pant diapers may include side panels that connect front and rear waist regions with each other. Thus, after being folded into a U about a lateral centerline in the same or similar way as conventional diapers, the side panels on pant diapers may connect the front and rear waist regions to form a waist opening and a pair of leg openings. In addition, the side panels may be laterally tucked inside the pant diapers before packaging.
Some currently available side panel tucker processes advance the pant diaper in a machine direction between upper and lower vacuum conveyors. In such configurations, the upper vacuum conveyor may apply an upward vacuum force to the front waist region of the pant diaper while the lower vacuum conveyor may apply a downward vacuum force to the rear waist region of the pant diaper. As such, the opposing vacuum forces hold the waist regions of the pant diaper apart from each other. Then, while the waist regions of the diaper are held apart by vacuum, a rotating tucker blade may be used to push the side panels into the interior of the diaper, creating longitudinal fold lines along the diaper. As such, some methods may rely on the location of the tucker blades relative the diaper to control the location of the longitudinal folds. Other methods may rely on the width of vacuum zones on the conveyors relative to the width of diaper to control the location of the longitudinal folds. However, with such methods, the locations of the longitudinal folds may be dictated in large part by the positions of the diapers relative to other equipment (e.g. conveyor, tuckers, etc.). Thus, the locations of the longitudinal folds in the diapers can be inconsistent due to varying positions of the diapers relative to such equipment during manufacture.